triangleztrianglez

So i replaced my coils yesterday as well as cleaned the throttle body with brake cleaner. The plate the the coils mount to is rusted more than Ive ever seen. The pin mounts were so rusted that uppon losing a bolt I snapped the thread in half. Had to drill the coils hole to allow the nut to grip. So 3 coils are new and an old one left on till I get a new bracket Tuesday.

Funny, it seems my car is running worse now for some reason...I think the spark plugs are the main issue cause the old coils didn't look too bad. Also reset my ecu. What are the side effects of doing that in terms of temporary car behaviour and mileage?

Mysterion

Guess you have learned one of the little things one should always remember when performing any sort of service on any car. Be ready for the unexpected and do everything in your power to avoid it. In this case, you should have soaked all the mounting hardware with penetrating oil the night before you replaced the coils. That way, the penetrant would have possibly loosened off the rust allowing safe removal of the hardware. When you go to pick up the new bracket, grab a can of a good pen oil at the same time (Liquid Wrench is a good one) and soak the mounting hardware for the bracket at least a couple of hours before you attempt to remove it. Another good trick is to apply anti-seize compound to all threads to prevent future rust issues. Just bear in mind that the main ingredient in steel is iron, the only metal that spends its entire existence attempting to return to its natural state...rust and dust.

poacherinthezoo

After resetting NVRAM (i.e. 20 brake stomps) the car will need to re-learn the fuel trims. Allowing the car to idle (10ish minutes once completely warmed up) will give the ECU the time it needs. The engine may sputter and experience idle dips/near stalls during this process.

04Green

iTrader: (1)

++ ^^ Start with it cold, and usually it will figure it out. If it really starts to hunt, turn on the AC, that calls for a higher idle speed. At least that is what I do. the process is very difficult with a warm engine, best to start cold.

triangleztrianglez

awesome thank you everyone for the advice! i unfortunately drove it after the reset (20 brake pumps) because i needed to get somewhere asap. ive driven it since and it seems to idle a bit more consistantly. the odd time i start it warm itll take a second or two longer before it starts up. should i reset it again still and let it idle for 15 minutes, cold?

one main thing that sounds different during a warm start than cold is theres not that *igniting* sound when the engine kicks on like it does when cold starting. still waiting on the spark plugs, the mileage is still terrible.. the mounting bracket as well as all 4 coils have been replaced after a grueling hour of trying to get the old rusted one off. it is the series 2 bracket which mean theres only two mounting holes that line up on the one side but not the other. it feels secure and sounds fine.

i noticed as well about the rattling sound coming from what sounds like my midpipe (directly below me slightly towards the back) and it sounds like a shard of metal that spazzes out when i give it a quick hard rev.. almost sounds like stepping on and crushing glass or a lightbulb but with the pitch of metal if that makes sense. im gunna assume the weak warm start is from my plugs and am trying to drive it as little as possible till i can inspect my cat and replace the wires and plugs.

Loki

iTrader: (1)

Could be nothing, could be your catalytic converter broke apart and the pieces are moving around. Better to drop the cat and inspect it visually, as mentioned earlier in the thread. Seriously, I know it's hard to not have a car, but it's going to be harder to need to replace the engine, you're asking for trouble driving a car in this condition.

Mysterion

One thing you might try that will only take a couple of minutes and a bit of arm stretching is take fair-sized stick (nothing too wimpy will work) and tap and poke at the catalytic converter shell. What you described sounds like it might be a heat shield loose. If that is the case, poking it with a stick might reproduce the rattle and if, indeed, it is loose, any good muffler shop should be able to tack it back solid with their mig welder. If this is the case, ask them to also check the emp variations between front and rear of the CAT. A large difference between the two ends will tell you there is something amiss and that you should drop the midpipe and check the CAT for damage.

Kim Jong Illest

Yes, I also have a low gas mileage problem. I just replaced my coils/plugs/wires @ 52,000km. I was having the jerkiness in 1st and second gear before 2.5k rpm and never had any CEL I did have unstable idle where it would drop to 750 and go back up to 850-950 instantly. Never had a check engine light even though one of the plug wires was completely burnt onto the ig coil. Now it never jerks unless I'm too hasty on the clutch; I can cruise at 1000-1500rpm in second gear without it jerking like it used to.

Still only getting around 280km for 50 liters which is around 13 mpg.

Already cleaned my MAF (was very clean so I don't suspect it's that or the throttle body).

Hope this helps.

triangleztrianglez

Interesting day.. Took the front left wheel off to inspect plugs and see if one wire came off but all seemed tight.

And FINALLY my buddy and I jacked the car up and took off the 3 bolts to the cat converter and also had to take the first exhaust (bracket?) off to bend the cat down further. Although it didn't budge much I was able to slip my phone in with its camera light on and snap a video of the honeycomb. Surprisingly there was not a single clogged hole which means my cat is in good shape thankfully.

Now for the interesting part- my heat shield is beyond rusted and broken in multiple places held unnefficiently by two hose clamps. For some reason the rattling sounds like it's coming from the mid-back end of my car not the mid front where the heat shield is.. Which leads me to believe that it may be the exhaust rattling against the first bracket. All I know is it's loud as hell and can be heard from across the street now.

Still waiting on the plugs and wires (Christmas shipping delays Woohoo) but if that fixes my mileage issue along with the warm start issues i'll be dumbfounded. Can't pin it on anything else at this point except a fuel line leak but I don't see it leaking anywhere..

I'll post pictures tomorrow of my cat and heat shield so you guys can see what I'm dealing with and if I missed anything important!

EpikYummeh

I wouldn't cruise under 2,000 RPMs but that's just me.

You could also check your eccentric shaft sensor (e-shaft sensor or ESS) and clean that if it's dirty. I posted some pictures of my cleaning here.

After you clean it you should clear your NVRAM by putting the ignition in the ON position (but don't start) and stomp the brake pedal 20 times within 8 seconds. If your car has the updated ECU flash (don't remember after what year it shipped on) you'll see the oil pressure gauge move across its range. Let the car idle for 5-10 minutes starting from COLD (temp gauge all the way left) so the ECU can re-learn your fuel trims.

Do you notice "rich" exhaust fumes? If not it might just be the way you drive it. Above 5,000 RPMs the car will consume more fuel as a second fuel injector activates, so if you drive above 5,000 RPMs for a considerable amount of time, that would explain the low mileage. I get about 16 MPG per tank with 30 miles of highway driving per week.

triangleztrianglez

I'll make sure to clean it when I change my plugs and wires. I do notice rich fumes actually. What could that be a sign of?

Loki

iTrader: (1)

Unburnt fuel, which would point to ignition difficulties.

Kim Jong Illest

I cleaned the ESS and did the 20 brake stomp but mileage is still bad however idle seems to be fixed at least from the ess reset. There is a rich gasoline smell how can I pinpoint the exact problem?

triangleztrianglez

Not trying to be rude or have a problem with hijacking threads but I think people are getting confused about who's who in this situation as both of ours are similar but we've taken different amount of steps hahah scroll through the posts on this thread and you may find your answer there!

Also, as Loki said the rich smell is unburnt fuel which means ignition problems so just as Im trying to do, change your plugs wires and coils and see if that works

EpikYummeh

Yep, definitely was confused as to who's who. Fortunately, the most common problems have shared solutions.

triangleztrianglez

Could not be more frustrated right now. Finally got the plugs and wires in the mail and replaced them. So at this point new coils wires and plugs as well as coil bracket and STILL it is sucking gas by the second. The warm start issue seems to be fixed but nothing else seems to fix my poor gas mileage. I'm out of ideas. I even filled my tires up with more air to 34psi cause they were at about 21.

Honestly ready to sell this thing. I can't even enjoy taking it for a cruise without losing a quarter tank in 30 kilometres.

Mysterion

At just under 6 mpg, the question arises : when you say "taking it for a cruise" what constitutes a cruise? Highway or city? Average speed and RPM? How much time idling in traffic, if city? Auto trans or Manual?

All ECU resets done and fuel trims relearned? Oxygen sensors plugged in tight? ESS, MAF and IAT clean?

If all that checks out as done/checked and ok, try running the car at a fast idle with the hood up and engine cover removed and sniff for fuel. While in there with engine idling high, listen for vacuum leaks/air leaks.

Best course of action is to treat us like sponges dying to soak up all the info you can offer. That makes it a LOT easier to try to help find the root cause of the problem

EpikYummeh

If you changed the coils and plugs, you shouldn't be running rich because all of the fuel mixture should be ignited by the fresh coil voltage and plugs. At this point if your mileage is still that bad, I would check for a leak. Put some cardboard under your car and let it sit for a while. If you don't see any wet spots on the cardboard then turn it on and let it idle, see if you get any leaks then.

Even if you go for a "cruise" and ride the RPMs pretty high, you shouldn't be getting mileage that bad.

Edit: Reading back through the thread, hearing that your heat shield was pretty well rusted through could suggest a leaky gas tank. Inspect the gas tank or leave some cardboard under it like I suggested.

muythaibxr

Running rich has nothing to do with the ignition system. It is about how much fuel is injected. A bad ignition system can keep it from burning as well though. A good ignition system isn't going to take a rich mixture and suddenly make it stoich, it is just going to burn it more completely.

That said, I agree that it sounds like there is a fuel leak or something of that nature.

EpikYummeh

I think the terminology is being used interchangeably here between a "rich smell" from the exhaust and "running rich." I meant a rich smell from the exhaust rather than running rich.